The invention relates to an inflatable seat, and more specifically to a ball-shaped seat.
Inflatable ball-shaped seats customarily consist of a gas or air-impermeable material, such as plastic, rubber or the like, are filled with air or gas and are used as ergonomic seats for working at a desk for example. Nevertheless, since it is the inherent function of the envelope of the ball-shaped seat not to allow air to pass through, thus not to be breathable, seating comfort is strongly restricted when used over an extended period of time. Another disadvantage is that because of its shape, the ball-shaped seat tends to roll away when not in use and in particular when the bottom surface on which it is standing is not horizontal.
DE-A 43 31 369 discloses a chair consisting of a ring and of a ball designed for sitting on, which is supported by said ring. The ball can be secured against falling down and rolling away by a coating. A similar solution is disclosed in U.S. Pat. No. 5,690,389, in which a ball-shaped body is fastened to a support. AT-U1995 also describes a chair having a ball fastened to the stand of a swivel chair. All these solutions have in common that the corresponding understructure is complicated and that seating comfort is not optimized.
It is the object of the invention to avoid these drawbacks and to achieve, on an inflatable seat of the type mentioned above, a simple structure while enhancing seating comfort.
The object of the invention is achieved with an inflatable ball-shaped seat formed of an envelope containing a gaseous medium, and a removable multilayered cover on the envelope, the cover defining an opening which enables a dome-shaped contact surface of the envelope to rest on a flooring surface. The materials of the cover are breathable. By using materials which are breathable and regulate the body climate, perspiration is considerably reduced, and subjective seating comfort is increased. Concurrently, rolling away is prevented from happening without having to provide a particular understructure. Moreover, the envelope may be readily withdrawn through the opening when the ball is deflated.
Seating comfort can be increased even further when the cover consists of several layers. In a particularly preferred embodiment of the invention, the cover is therefore provided with an inner lining and an outer skin, a filling being preferably arranged between the inner lining and the outer skin. The outer skin of the cover advantageously is fabricated from leather, fabric or any other material which is breathable and regulates the body climate. A material which is breathable and regulates the body climate, preferably inwoven sheep""s wool, is used for the filling too. The inner lining may be made of fabric and its primary function is to achieve a good bond between the cover and the envelope of the ball-shaped seat.
In another embodiment of the invention there may be provided that the cover surrounds the envelope of the seat except for a dome-shaped contact surface of the seat""s envelope. Thanks to the dome-shaped sparing of the cover in the area of the contact surface of the seat, a good bond with the bottom surface is achieved. It is particularly advantageous when the cover is provided with a ring-shaped reinforcement which is preferably accommodated in the area of the rim on the boundary to the dome-shaped contact surface. The ball-shaped seat may thus be efficiently prevented from unintentionally rolling away. The ring-shaped reinforcement is thereby provided with an inserted, preferably ring-shaped border-strengthening means which is preferably made of leather, rubber or plastic.